MCP servers

Model Context Protocol (MCP) lets you connect external tool servers to the AI agent. MCP tools extend the agent’s capabilities beyond the built-in tools.

Built-in MCP server

BRICKS projects include a built-in bricks-ctor MCP server that is automatically configured during bun install. It provides tools for compiling, previewing, searching icons and Lottie animations, selecting Hugging Face models, and managing media assets.

bricks-ctor built-in MCP server

See the full tool reference in the bricks-ctor docs.

When the bricks-ctor server runs inside CTOR, its preview tool is suppressed so the agent uses the embedded Simulator pane instead — screenshots match what you see in the pane, and a single simulator handles both the visible preview and agent captures. Other agents (Claude Code, Codex, the CLI) keep using the MCP preview tool as usual.

Configuration

MCP servers are configured in a .mcp.json file in your project root:

{
  "mcpServers": {
    "my-server": {
      "command": "npx",
      "args": ["-y", "some-mcp-server"],
      "env": {
        "API_KEY": "your-api-key"
      }
    }
  }
}

Transport types

stdio

Spawns the MCP server as a child process that communicates over stdin/stdout.

{
  "mcpServers": {
    "my-server": {
      "command": "npx",
      "args": ["-y", "some-mcp-server"],
      "env": {}
    }
  }
}

Field	Description
`command`	The command to run
`args`	Array of command arguments
`env`	Environment variables for the process

HTTP

Connects to a remote MCP server over HTTP.

{
  "mcpServers": {
    "remote-server": {
      "url": "https://mcp.example.com/sse"
    }
  }
}

Field	Description
`url`	The server endpoint URL

Managing MCP servers

Open the Plugins panel from the sidebar and switch to the MCP tab. The panel shows:

A list of configured servers with their connection status
Green dot — connected, with the number of available tools
Red dot — disconnected or errored
An expandable tool list for each server

Edit configuration

The MCP panel includes a config editor where you can edit your .mcp.json directly. Click Save to apply changes and Reconnect to re-establish server connections.

Scopes and inheritance

The MCP panel has a Project | Global switcher. Global edits the main workspace’s .mcp.json, and those servers are inherited by every project. When a project defines a server with the same name as a global one, the project entry wins. Each project has an Inherit global MCP servers toggle that controls whether global servers are pulled in. Inherited servers appear with a Global badge. Servers installed by plugins show a Plugin badge. They live in a machine-local registry, are never written to your project’s .mcp.json, and require your consent before they run. When servers share a name, precedence runs from lowest to highest: plugin, then inherited, then project.

Tool integration

Once connected, MCP tools appear alongside the built-in tools. The agent can discover and call them like any other tool. Tool results support both text and image content. MCP server connections are cached per project and cleaned up automatically when the app quits.

Getting started

Working with projects

Ship your app

Reference

Changelog

Built-in MCP server

bricks-ctor built-in MCP server

Configuration

Transport types

stdio

HTTP

Managing MCP servers

Edit configuration

Scopes and inheritance

Tool integration

​Built-in MCP server

bricks-ctor built-in MCP server

​Configuration

​Transport types

​stdio

​HTTP

​Managing MCP servers

​Edit configuration

​Scopes and inheritance

​Tool integration

Built-in MCP server

Configuration

Transport types

stdio

HTTP

Managing MCP servers

Edit configuration

Scopes and inheritance

Tool integration